The Spiral
The Spiral is an unknown entity or force that brutally wipes out the entire population of Kurôzu-Cho every few centuries or millenia, at irregular intervals. It seems to be able to infect, and then control, the minds and bodies of humans. From what is shown in the manga, the Spiral can only be seen, heard, or felt, by people who are cursed (with the exception of Shuichi Saito). The identity and nature of the Spiral are unknown, though it does seem to be sentient to an extent, as shown when it repeatedly takes an interest in Kirie (and to a lesser extent, Shuichi). It may or may not originate from the City of Spirals underneath Kurôzu-Cho. Whether the Spiral is a curse, an infection, a being, or a force, is completely unknown. It is confirmed that the Spiral only affects Kurôzu-Cho, and follows a pattern when killing off the town: first come the "random" deaths and disappearances, and "strange" cases of obsession with the pattern, then come more severe effects such as multiple hurricanes and tornadoes, then the town becomes an inescapable pile of rubble, until finally, Kurôzu-Cho is rebuilt as a giant spiral row-house and everyone inside is sucked into the City of Spirals. In the movie, the spiral is shown as being less sentient than in the manga, and targets mainly Kirie. It also has a lesser effect on the plot than in the manga. The pattern of deaths is limited to the first stage; loosely spiral-related deaths and disappearances, followed by a huge wave of deaths which wipe out the town. It does not seem to be able to forcbly keep people inside the town. Abilities Being a nearly omnipotent force, the Spiral can control the minds and bodies of humans and animals. It can also bend nature and the laws of physics to its own will, as it demonstrates constantly. As demonstrated in chapters 3( the Scar) and 20 (Galaxies), the Spiral can also grant humans supernatural abilities before killing them. As also demonstrated in chapter 20, it is capable of telepathic communication with humans, and may be present throughout the entire universe and capable of controlling entire galaxies. The Spiral can control the weather, atmosphere, and air pressure inside Kurozu-Cho, as well as the ocean within the town's limits. It can use stones and bricks to produce a scorching light (see chapter 9). As shown in chapters 14 (Butterflies) and onwards, the Spiral is able to effectively close Kurozu-Cho from being entered or exited. In the movie, the Spiral is significantly less powerful; it seems less skilled at infecting people's minds than their bodies, is not sapient in any way and thus cannot communicate, cannot affect the abilities of humans, and is confined entirely to Kurozu-Cho with no implication of controlling other galaxies. It can control the clouds, but not the rest of the weather or air pressure, and can only control the water in Dragonfly Pond as opposed to the ocean. Additionally, the Spiral seems not to be able to control animals or plants; only humans. It is also incapable of forcibly making the town impossible to leave. Immunity While most characters who became contaminated died within a few days, some people seem to have a heightened immunity to the Spiral. A few such people being: Shuichi Saito, who was fully capable of seeing and interacting with the Spiral without ever becoming contaminated, Kirie and Yasuo Goshima, who were contaminated multiple times and recovered, and Mrs Goshima, who was contaminated once and recovered. Whether this immunity is natural or achieved somehow is entirely unknown, though in the case of the Goshimas, is is very likely that it is natural, as they knew nothing of the Spiral. There are many fan speculations as to why Shuichi is completely immune.